#!/usr/bin/env bash
#
# checkout files/commit/branches using fzf
#
# @params
# Globals
#   ${mydir}: current directory of the script, used for imports
#   ${all_files}: search all tracked files instead of just the modified files
#     and then select a specific commit to checkout against 
#   ${branch}: checkout branch
#   ${commit}: checkout commit
#   ${selected_branch}: selected_branch to switch
#   ${selected_files}: selected_files to checkout to the version in HEAD
#   ${selected_commit}: selected commit to checkout
#   ${confirm}: confirm status of the user
# Arguments
#   -h: show help message
#   -a: search all files instead of just the modified files
#   -b: search branch and checkout branch
#   -c: search commit and checkout commit

set -e
set -f

mydir="${0%/*}"
source "${mydir}"/../helper/set_variable.sh
source "${mydir}"/../helper/get_confirmation.sh
source "${mydir}"/../helper/git_query.sh

function usage() {
  echo -e "Usage: dotbare fcheckout [-h] [-a] [-b] [-c] ...\n"
  echo -e "Checkout files/commit/branch using fzf"
  echo -e "By default, checkout files back to HEAD (Reset changes back to HEAD)\n"
  echo -e "optional arguments:"
  echo -e "  -h\tshow this help message and exit"
  echo -e "  -a\tsearch all files and select a commit to checkout for selected files"
  echo -e "  -b\tcheckout branch"
  echo -e "  -c\tcheckout commit"
}

all_files=""
branch=""
commit=""

while getopts ":habc" opt
do
  case "$opt" in
    a)
      all_files='true'
      break
      ;;
    b)
      branch='true'
      break
      ;;
    c)
      commit='true'
      break
      ;;
    h)
      usage
      exit 0
      ;;
    *)
      echo "Invalid option: ${OPTARG}" >&2
      usage
      exit 1
      ;;
  esac
done

if [[ -n "${branch}" ]]; then
  # checkout branch
  selected_branch=$(get_branch 'Select a branch to checkout')
  [[ -z "${selected_branch}" ]] && exit 0
  /usr/bin/git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" checkout "${selected_branch}"
  exit 0
elif [[ -n "${commit}" ]]; then
  # checkout commit
  selected_commit=$(get_commit 'Select a commit to checkout')
  [[ -z "${selected_commit}" ]] && exit 0
  /usr/bin/git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" checkout "${selected_commit}"
  exit 0
else
  # checkout files (reset file changes back to HEAD)
  if [[ -z "${all_files}" ]]; then
    selected_files=$(get_modified_file 'select a file to checkout version in HEAD' | tr '\n' ' ')
    [[ -z "${selected_files}" ]] && exit 0
    echo "(dryrun) dotbare checkout -- ${selected_files}"
    confirm=$(get_confirmation "Confirm?")
    [[ "${confirm}" != 'y' ]] && exit 0
    # shellcheck disable=SC2086
    /usr/bin/git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" checkout -- ${selected_files}
  else
    selected_files=$(get_git_file 'select a file to checkout' | tr '\n' ' ')
    echo "${selected_files}"
    [[ -z "${selected_files}" ]] && exit 0
    # continue select a commit and then checkout the file back to the selected commit
    selected_commit=$(get_commit 'select the target commit' "${selected_files}")
    [[ -z "${selected_commit}" ]] && exit 0
    echo "(dryrun) dotbare checkout ${selected_commit} -- ${selected_files}"
    confirm=$(get_confirmation "Confirm?")
    [[ "${confirm}" != 'y' ]] && exit 0
    # shellcheck disable=SC2086
    /usr/bin/git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" checkout "${selected_commit}" ${selected_files}
  fi
fi